walsh



( o Model.)

J.WALSH, T. P

2Sheets-Sheet 1. MURPHY & E. A. CLARK.

LEVEL.

7 PatGHtGd-May 5, 18 flg-z.

WITNESSES v g, I

INVENTOR %%Q a 1%? JAM/m ATTORNEYS.

(No Model.) 2 Sheets-Sheet 2. J. WALSH, T. F. MURPHY 8v E. A. CLARK;

' 'LEVEL.

No. 317,250. Patented May 5, 1885.,

WITNESSES I INVENTOR:

66/; 42% BY mm 06- ATTORNEYS.

UNITED STATES PATENT OFFICE.

JAMES WALSH, THOMAS F. MURPHY, AND EVERETT A. CLARK, OF NORTH ADAMS, MASSACHUSETTS; SAID CLARK ASSIGNOR TO SAID \VALSH AND MURPHY.

LEVEL.

. JFECIFICATION forming part of Letters Patent No. 317,250, dated May 5, 1885.

Application filed July 28, 1884. (No model.)

To all whom it may concern.-

Be it known that we, JAMES WALsH, THOMAS F. MURPHY, and EVERETT A. CLARK, of North Adams, in the county of Berkshire,

. and State of Massachusetts, have invented a new and Improved Level, of which the followcury contained in the said cap, whereby whenthe float is inclined the mercury will seek its .level, and will act on the float and turn the hand more or less.

The invention also consists in the combination, with the above-mentioned hand and dial, of a cog-wheel mounted on the same pivot with the hand, and engaging with a pinion mounted on a shaft carrying a smaller dial, for the purpose of indicating the fractions of degrees.

Reference is to be had to the accompanying c drawings, forming part of this specification, in which similar letters of reference indicate corresponding parts in all the figures.

Figure 1 is a longitudinal elevation of my improved level, parts being broken out. Fig.

5 2 is an enlarged side view of the dials, the cap being swung from the dial. Fig. 3 is a crosssectional elevation on the line a; m, .Fig. 2. Fig. 4 is a detail view of the float; Fig. 5 is a detail view of the gearing. Fig. 6 is a lon- 4o gitudinal sectional elevation of the level on the line y y, Fig. 7, showing a modification of the wheel and pinion. Fig. 7 is a crosssectional elevation of the same.

The usual-bar, A, has its edges provided with angle-strips, orhas them chamfered, and

is provided with a recess, B, for receiving the float.

In the recess B a closed circular cup, 0, is placed, which contains a semicircular float, D, fitting closely in the cup and mounted on a pivot, E, which is journaled in the sides of the cup and projects from the front of the same, and is also journaled in a plate, F, covering the recess B and the circular cup 0.

The remaining part of the circular cup is filled with mercury, and the straight edge of the float D is provided with a series of notches or recesses, g, to compensate for contraction and expansion of the mercury on account of changes in temperature. The circular cup 0 is held to a plate, G.

On the outer side of the plate G a fiat box, 1

H, is riveted, which box is held between the plate G and the outer plate, F.

Vithin the flat box H a cog-wheel, I, is mounted on the pivot E, which cog-wheel engages with a pinion, J mounted on a pivot, K, journaled in the plate G and in the front of the flat box H. The diameters of the cogwheel I and the pinion J are in such relation to each other that the said pinion makes twenty-four revolutions to every revolution of the cog-wheel.

011 the plate F a dial, L, is produced, the center of which is the pivot E, and the dial being divided into three hundred and sixty degrees, which are subdivided into four quadrants of ninety degrees each.

On the outer end of the pivot E a hand, M, is securely mounted, which is adapted to revolve over the dial L. On the dial L a smaller dial at N is formed, which is divided into fifteen degrees, each degree in turn being divided into ten parts. A hand, 0, secured to the outer end of the pivot K, revolves over the dial N.

A crystal, 1?, covering the dials, is held over the same and in a face-plate, Q, which is sooured on the outer surface of the bar A.

A cap, R, adapted to cover the dial L, is

hinged to theplate Q. This cap or cover may be dispensed with, if desired. The bar A is also provided with a handle, S, which can be secured in a recess in the top edge of the said bar, or part of the bar can be cut out to form the handle. This handle is preferably so arranged that it will be at the center of gravity of the bar, and the dial, float, and other parts above described are arranged at one side of the same.

The float D can be made of wood, metal, or any other suitable material, either solid or hollow. The other parts, in which the cap containing the float, the gearing, &c. are held, are preferably made of brass.

For the purpose of avoiding the backlash of the small hand 0, we have provided the device shown in Figs. (5 and 7. In place of mounting a single wheel, I, on the pivot E, we provide two wheels, I and I, both having precisely the same diameter and the same number of teeth, and both engaging: with the pinion J. Of the two cog-wheels I and I, the former is rigidly mounted on the shaft,whereas the latter isloosely mounted. A flat spiral spring, IV, has one end secured on the wheel I, and the other'end is secured to the pivot E, so that all movements of the pivot E will. be immediately transmitted by means of the spring I to the wheel I. The spring W at all times holds the teeth of the wheel 1 in contact with the teeth of the pinion J, so that at the slightest movement of the float D the hand 0 will move correspondingly. This is a matter of great importance, as by the more or less lost motion great inaccuracy is caused in levels. The pinion is always moved from the cogwheel I, the cog-wheel I and the spring serving only to keep the teethin contact and preventing the lost motion.

The operation is as follows: The float is so adjusted in relation to the hand M and the dial L that when the bar A is level the hand M points to zero. If one end or the other of the bar A is raised, the mercury T in the cup 0 will seek its level, and thus will turn the float D more or less, and as the hand M is mounted on the same pivot with the float the said hand will be turned more or less toward the right or left, and thus will indicate the distance that the bar A is out of level. By the time that the hand M has been moved fifteen degrees the hand 0 will have completed one revolu tion. The subdivisions of degrees are shown very distinctly and accurately by the hand 0 on the small dial N. In the same inannerthat the above-described device is used as a level it can be used as an inclinometer or apparatus for showing the inclination.

The advantages of the above-described i11- strument are, that it not only operates very rapidly, but it clearly indicates the number of degrees of inclination. The cap Rprotects the crystal 1? from injury and from moisture, dust, &c.

For ordinary levels we intend to use the two dials only that are shown in the draw ings; but for large inclinometers we intend to increase the speed of the smaller pointer or hand, and to divide its circle into sixty parts, so as to indicate sixty minutes or one degree for each revolution. Then the two pointers will indicate degrees and the minutes between them. In some levels the small pointer can be dispensed with entirely.

If desired, the cup 0 may be dispensed with, and the float and mercury placed in the cavity in the bar.

'Having thus described our invention, what we claim as new, and desire to secure by Letters Patent, is

1. In a level, the combination, with the bar having a cavity containing a float and a liquid for acting on the float, of a pivot on which the float is mounted and a hand mounted on the said pivot, substantially as herein shown and described.

2. In a level, the combination, with a bar having a cavity containing a liquid and a float, of a pivot on which the float is mounted, a hand on the outer end of the said pivot, and a dial below the hand, substantially as herein shown and described.

3. In a level, the combination, with a bar, of a circular cup containing a semicircular or like float fitting closely in the same, and having notches in the straight edge, mercury contained in the cup, a pivot on which the float is mounted, and a hand or pointer on the said pivot, substantially as herein shown and described.

4:. In a level, the combination, with the dial, of a hand adapted to revolve over the dial and mounted on a suitable pivot, devices for revolving the said pivot by the action of gravitation, a cog-wheel mounted on the said pivot, and engaging with a pinion on a pivot carrying a smaller hand revolving over a smaller dial, substantially as herein shown and described.

5. In a level, the combination, with the bar A, of the cup 0, containing the float D, the pivot E, on which the float D is mounted, the hand M on the end of the pivot, the cog-wheel I on the pivot E, the pivot K, the pinion J on the same, which pinion engages with the cogwheel I, and the hand 0 on the said pivot, substantially as herein shown and described.

6. In a level, the combination, with the bar A, of the cup 0, containing the float D and the mercury T, the pivot E, the hand M, mounted on the same, the dial. L, on which a smaller dial, N, is produced, the cog-wheel I on the pivot E, the pinion .T on the pivot K, and the hand 0 on the said pivot K, substantially as herein shown and described.

7. In a level, the combination, with a pivot acted upon by a weight, pendulum, or float, of two cog-wheels of like size, of which one is mounted rigidly and the other loosely on the said pivot, a pinion with which the two cogwheels engage, a hand on the pivot of the pin- IIO ion, and a spiral spring connected with the ion with which the two cog-wheels engage, 1o loose cog-wheel and with the pivot, substanand a hand on the pivot of the pinion, subtially as herein shown and described. I stantiallyas herein shown and described.

8. In at level, the combination, with the JAMES \VALSH. pivot acted upon by a float, pendulum, 810., THOMAS F. MURPHY. of two cog-wheels of like size on the pivot, of EVERETT A; CLARK. which one is mounted loosely and the other Vitnesses: rigidly, the loose wheel being connected by a A. XV. PRESTON, suitable spring device with the pivot, a pin- WILLIAM; B. PYNE. 

